Survey of aflatoxin contamination in peanut products in Taiwan from 1997 to 2011

Aflatoxins are toxic, mutagenic, and carcinogenic compounds that contaminate various types of foods and feedstuffs. The aflatoxin levels in various kinds of peanut products in Taiwan were surveyed during the recent decade. A total of 1827 commercial peanut products were collected from different regions of Taiwan from 1997 to 2011. The samples were cleaned by immunoaffinity columns and analyzed for aflatoxins B1, B2, G1, and G2 by high-performance liquid chromatography with fluorescence detection. Aflatoxins were detected in 32.7% of samples with levels ranging from 0.2 μg/kg to 513.4 μg/kg. Peanut butter had the highest aflatoxin-positive incidence, followed by peanut flour, peanut candy, rice syrup, and peanuts. In addition, 6.8% of the samples had total aflatoxin concentrations (i.e., the sum of B1 + B2 + G1 + G2) that were higher than the Taiwan regulatory limit of 15 μg/kg. Among the aflatoxin-positive samples, aflatoxin B1 had the highest frequency of detection, followed by aflatoxin B2, aflatoxin G2, and aflatoxin G1. This longterm survey provides valuable information on aflatoxin contamination in peanut products marketed in Taiwan.